Backup restore mysql from query of single table - mysql

I have a database with three tables .
I want to create a backup file of some records in the second table :
mysqldump --opt --user=${USER} --password=${PASS} --databases ${DATABASE} --where="id = $1" mydb Table2 > FILE.sql
the problem is in the restore by using this code .
mysql --user=${USER} --password=${PASS} ${DATABASE} < FILE.sql
It deletes the entire database and inserts I only selected records from the previous code .
I wish only the selected records restore without deleting the rest .

You are using the [--databases][1] flag which is used when dumping several databases and should not be used when you want to dump only a single table.
Dump several databases. Normally, mysqldump treats the first name
argument on the command line as a database name and following names as
table names. With this option, it treats all name arguments as
database names. CREATE DATABASE and USE statements are included in the
output before each new database.
Avoid using that argument and for good measure use --no-create-info or simply -t instead to make sure create table / drop table commands are not in the dump file

You should try using the --skip-add-drop-table option when using mysqldump.
http://dev.mysql.com/doc/refman/5.5/en/mysqldump.html
This would prevent a drop table entry being added to the sql export.

Related

MySQL import - How to ignore Drop table if exists line?

I exported 2 identical databases(identical in terms of names and structures of tables) into two .sql files using mysqldump. I want to merge them into one file. However, both the databases have a 'Drop table' line before every table. What that means is if I import db1 and then db2, db1 tables are dropped before db2 tables are imported.
The files are huge and I am not able to open them in the editor. Also, there are 50 tables in each databases.
How can I ignore the Drop table command during mysql import?
All you need is to add --skip-add-drop-table option when using mysqldump.
$ mysqldump --databases --skip-add-drop-table -u root db1 > /tmp/qqq.2
So, there would not DROP TABLE IF EXISTS in sql files.
see docs of mysql on --skip-add-drop-table
If you do not want to make dump once again and you are using Linux you can go with:
awk '!/^DROP TABLE IF EXISTS/{print}' <dump.file> | mysql <db_name>
If you want to dump data once again you should pass --skip-add-drop-table to mysqldump utility.
I guess I don't see why a DROP TABLE statement should be problematic or why you need to merge dumps for two IDENTICAL databases.
That being said, you should probably just not add DROP TABLE in the initial dump. This would be controlled via flag use in your mysqldump command as noted in the documention at http://dev.mysql.com/doc/refman/5.5/en/mysqldump.html
This probably means you need to use --skip-opt flag if you were using default options (default is to run as if --opt flag is passed). You will then need to specify all flags within --opt that you still want to use.

mysqlimport using dump

I need to restore a dumped database, but without discarding existing rows in tables.
To dump I use:
mysqldump -u root --password --databases mydatabase > C:\mydatabase.sql
To restore I do not use the mysql command, since it will discard all existing rows, but instead mysqlimport should do the trick, obviously. But how? Running:
mysqlimport -u root -p mydatabase c:\mydatabase.sql
says "table mydatabase.mydatabase does not exist". Why does it look for tables? How to restore dump with entire database without discarding existing rows in existing tables? I could dump single tables if mysqlimport wants it.
What to do?
If you are concerned with stomping over existing rows, you need to mysqldump it as follows:
MYSQLDUMP_OPTIONS="--no-create-info --skip-extended-insert"
mysqldump -uroot --ppassword ${MYSQLDUMP_OPTIONS} --databases mydatabase > C:\mydatabase.sql
This will do the following:
remove CREATE TABLE statements and use only INSERTs.
It will INSERT exactly one row at a time. This helps mitigate rows with duplicate keys
With the mysqldump performed in this manner, now you can import like this
mysql -uroot -p --force -Dtargetdb < c:\mydatabase.sql
Give it a Try !!!
WARNING : Dumping with --skip-extended-insert will make the mysqldump really big, but at least you can control each duplicate done one by one. This will also increase the length of time the reload of the mysqldump is done.
I would edit the mydatabase.sql file in a text editor, dropping the lines that reference dropping tables or deleting rows, then manually import the file normally using the mysql command as normal.
mysql -u username -p databasename < mydatabase.sql
The mysqlimport command is designed for dumps created with the mysql command SELECT INTO OUTFILE rather than direct database dumps.
This sounds like it is much more complicated than you are describing.
If you do a backup the way you describe, it has all the records in your database. Then you say that you do not want to delete existing rows from your database and load from the backup? Why? The reason why the backup file (the output from mysqldump) has the drop and create table commands is to ensure that you don't wind up with two copies of your data.
The right answer is to load the mysqldump output file using the mysql client. If you don't want to do that, you'll have to explain why to get a better answer.

How to take Mysql Backup without using script?

Is it possible to take daily backup (Only the records per day) for particular table in DB.Once the backup is done need to delete those records from table.
Is this scenario will work without using scripting language like php,perl...?
the easiest way is to use script
1) select records you need
2) put them in some form of dump
3) run delete from table with parameters you need
other constructions (triggers with stored procedures or else), IMHO, will shoot you in leg eventually
mysqldump -u root -p db_name > db_backup.sql
using above command we can back up database and if you want to take the back up of a seleted table you can use : mysqldump -c -u -p db_name table_name > table_backup.sql
And to drop the db use drop database db-name and to drop a specific table use drop table table-name

mysqldump extracting data without table structure

I'm trying to dump all of my mysql data for one database into a single file. That said, I don't want to include the table structures in this file (there is another file which will have the structure of the tables in it).
Is it possible to strictly extract the data and not the table structures?
What I am doing right now ...
# Extracts the database structure
mysqldump -d -hlocalhost -uusername -ppassword database -r database.sql
# Extracts each table and their data individually
mysqldump -d -hlocalhost -uusername -ppassword database --tab .
The first command will spit out a .sql file with the structure of all entities in the database whereas the second one automatically makes the .sql and .txt files with the structure and entities split out.
What I need is one copy of the entire database which is done the same way.
Thanks
Use the --no-create-info option, or its shorthand -t:
--no-create-info, -t
Do not write CREATE TABLE statements that re-create each dumped table.
Note
This option does not not exclude statements creating log file groups or tablespaces from mysqldump output; however, you can use the --no-tablespaces option for this purpose.

Mysql restore to restore structure and no data from a given backup (schema.sql)

Hi I use mysql administrator and have restored backup files (backup.sql). I would like to use restore the structure without data and it is not giving me an option to do so. I understand phpadmin provides this. I can not use this however. Any one can tell me an easy way?
Dump database structure only:
cat backup.sql | grep -v ^INSERT | mysql -u $USER -p
This will execute everything in the backup.sql file except the INSERT lines that would have populated the tables. After running this you should have your full table structure along with any stored procedures / views / etc. that were in the original databse, but your tables will all be empty.
You can change the ENGINE to BLACKHOLE in the dump using sed
cat backup.sql | sed 's/ENGINE=(MYISAM|INNODB)/ENGINE=BLACKHOLE/g' > backup2.sql
This engine will just "swallow" the INSERT statements and the tables will remain empty. Of course you must change the ENGINE again using:
ALTER TABLE `mytable` ENGINE=MYISAM;
IIRC the backup.sql files (if created by mysqldump) are just SQL commands in a text file. Just copy-paste all the "create ..." statements from the beginning of the file, but not the "insert" statements in to another file and "mysql < newfile" you should have the empty database without any data in it.
there is no way to tell the mysql client to skip the INSERT commands. the least-hassle way to do this is run the script as-is and let it load the data, then just TRUNCATE all of the tables.
you can write a script to do the following:
1 : import the dump into a new database.
2 : truncate all the tables with a loop.
3 : export the db again.
4 : now u just have the structure
You can backup you MYSQL database structure with
mysqldump -u username –p -d database_name > backup.sql
(You should not supply password at command line as it leads to security risks.MYSQL will ask for password by default.)